The present invention relates to substrate processing methods for substrate processing facilities.
The substrate processing method for this purpose is for manufacturing processed substrates by storing in storage shelves containers, each of which vertically holds a plurality of substrates such as glass substrates used for liquid display devices or plasma display devices aligned at certain intervals, subsequently transferring the stored containers to a substrate loading/unloading section of each substrate processing device with a container transfer device, and subsequently performing prescribed processes such as such as coating, exposure and developing, on substrates stored in the containers in a plurality of substrate processing devices. Also in the substrate processing method, when any time lag occurs in processing a certain substrate while the containers are sequentially transferred to the substrate loading/unloading section of the substrate processing device due to variance in the processing amount among substrate processing devices, the container that stores the certain substrate is temporarily stored in the storage shelf with the substrate stored therein.
One conventional example of such substrate processing methods is as described below. Conventionally, a clean air ventilation means for transfer area that performs ventilation with clean air (or filtered air) in order to maintain purity of a substrate transfer area where a substrate transfer device transfers substrates between the substrate loading/unloading sections and the substrate processing devices is provided, the container is formed in a quadrangular tube shape turned over sideways, an opening on one end side thereof serving as an entrance for loading and unloading the substrates, a fan filter unit that performs ventilation from an opening on the other end side to the entrance of the container is provided in an opening portion on the other end side of the container, and purity of the substrates is maintained by performing ventilation with the fan filter unit when the container is transferred by the container transfer device, and operation of the fan filter unit is stopped when the substrates are transferred to or from the substrate loading/unloading section with the substrate transfer device (see for example, JP 2001-308169A).
Even when the substrates are stored in the storage shelf, purity of substrates can be maintained by ventilating the container with the fan filter unit. In addition, by maintaining purity of the substrate transfer area with the clean air ventilation means for transfer area, purity of the substrates that are removed from the container and transferred in the substrate transfer area is maintained.
In the above-described conventional substrate processing method, when the container is stored in the storage shelf and transferred with the container transfer device, by performing ventilation with clean air from an opening on the other end side toward the entrance of the container with the fan filter unit, the clean air being discharged from the entrance, dust present inside the container is prevented from attaching to the substrate and also, outside air is prevented from entering inside the container even when airflow around the container is disturbed due to operation of the container transfer device or the like, thereby maintaining purity of substrates in the container.
However, when ventilation is performed when the container is stored in the storage shelf and is transferred with the container transfer device, if ventilation is performed with the fan filter unit, although the speed of air inside the container may be comparatively low as long as dust present inside the container is prevented from attaching to substrates, it is necessary to set the speed of air discharged from the container comparatively high in order to prevent back flow of the outside air from the entrance. For this reason, the ventilation flow rate of the fan filter unit is increased so as to keep the speed of air discharged from the container comparatively high, and moreover, the ventilation with the fan filter unit is continued for a long period that is total of time required to store the container in the storage shelf and time required to transfer the container with the container transfer device. Therefore, the running cost of the fan filter unit is increased, which increases the cost to manufacture processed substrates.
Also, when substrates are transferred in the substrate loading/unloading section with the substrate transfer device, operation of the fan filter unit is stopped. Therefore, clean air in the substrate transfer area enters inside the container, with which dust caused by the substrate transfer device sometimes enters inside the container through the entrance thereof, and therefore substrates inside the container are liable to be soiled by dust that thus enters the container.